Overview of endocrinology Flashcards
State hypothalamic hormone which controls secretion of GH?
GHRH Increases
Growth hormone releasing hormone (GHRH)
GHIH/somatostatin Decreases
GHIH= Growth hormone inhibiting hormone
Describe the half life in cirulation and transport of tyrosine deriv (CA’s),
thyroid hormones?
HL= Seconds (CA), Hours (thyroid) T= Thyroid bound to plasma proteins
CA= catecholamines
State secretions in thyroid gland
Thyroxine, tri-iodothyronine
State hypothalamic hormone which controls secretion of TSH?
TRH (thyroid releasing hormone) Increases
Somatostatin (GHIH) (Growth hormone inhibitng hormone) Decreases
State the 3 general functions of hormones?
- Reproduction, growth and development
- Maintenance of internal environment
- Energy production, utilization and storage
State the 4 chemical classifications of hormones?
Protein/peptide
Steroid (cholestrol)
Amino acid derivative (tyrosine/tryptophan)
Fatty acid derivative
State secretions of the adipose tissue?
Leptin
State the hormones secreted via the anterior lobe of the pituitary gland?
These are all trophic hormones (cause stimulation of other glands):
GH (Growth hormone)
prolactin
TSH (Thyroid stimulating hormone
ACTH (Adrenocorticotrophic hormone
LH/ FSH (Luteinizing hormone (LH) and
Follicle stimulating hormone (FSH) )
Remember via ‘ FAT PEG’
State the hormones involved in maintenance of internal environment?
Aldosterone, parathyroid hormone, vitamin D
Describe the Paracrine signalling mechanism
Hormones released by endo. cells which act locally on
adjacent cells
Name the 8 major endocrine glands
- Hypothalamus
- Pituitary gland
- Thyroid
- Adrenal cortex
- Gonads
- Pancreas
- Parathyroid glands
State the hormones involved in energy production, utilization and storage?
Insulin, glucagon, thyroid hormones, cortisol, growth hormone
Describe the autocrine signalling mechanism
Hormones released by a cell which act back on the same cell
State the secretions involved within the regions of the adrenal
gland
Cortex: Cortisol, aldosterone
Medulla: Adrenaline/noradrenaline
State 6 examples of steroid hormones?
Cortisol
Aldosterone
Oestrogens
Androgens
Progestagens
Vitamin D
State the secretions involved within the regions of the pituitary
gland
Anterior lobe - trophic hormones
Posterior lobe – oxytocin & vasopressin (ADH)
State secretions in Pancreas
Insulin, glucagon
State hypothalamic hormone which controls secretion of Prolactin?
Dopamine Decreases
(Dominant control)
Describe how hormones from the anterior pituitary lobe released?
Along the hypothalamic-pituitary axis
Other neurosecretory cells in the hypothalamus release their hormones into the portal capillaries
These are transported directly to endocrine cells of the anterior pituitary gland
This stimulate secretion of the AP hormones
State the hormones involved in repro., growth and development?
Sex Steroids, thyroid hormones, prolactin, growth hormone
State 3 examples of FA derivatives hormones?
Prostaglandins
Thromboxanes
Prostacyclin
FA= Fatty acid
Excess GH?
Acromegaly
Describe the half life in cirulation and transport of steroid hormones?
HL= Hours- days T= Bound to plasma proteins
State 5 examples of protein/peptide hormones?
Hypothalamic hormones
Pituitary hormones
Insulin
PTH
Calcitonin
Describe the half life in cirulation and transport of protein/peptide hormones?
HL= Minutes T= Mainly unbound
State hypothalamic hormone which controls secretion of ACTH?
CRH (Corticotrophin releasing hormone) Increases ACTH
State the 4 signalling mechanisms within the endocrine system
Endocrine
Paracrine
Autocrine
Intracrine
Excess of cortisol?
Cushing’s disease
State secretions in gonads
Oestrogens, androgens, progestagens
State the hormones secreted via the posterior lobe of the pituitary gland?
Oxytocin
Vasopressin (ADH)
State secretions of the thymus gland?
Thymic hormones
State secretions of CVS (cardiac muscle cells)?
ANP (atrial natrieutic hormone)
Endothelins
State 4 examples of AA derivatives hormones?
Adrenaline
Nor-adrenaline (tyrosine)
Thyroid hormones (tyrosine)
Melatonin (tryptophan)
AA= Amino acid
State secretions of the pineal gland?
Melatonin
Describe how hormones from the posterior pituitary lobe released?
Along the hypothalamic-pituitary axis
Magnocellular neurones in the hypothalamus synthesise the posterior pituitary hormones, where they send it
to the posterior lobe along nerves and release from the posterior lobe of the PG
State the 3 glands controlled by the hypothalmic-pituitary axis with the hormone
that stimulates it?
Thyroid (TSH)
Adrenal cortex (ACTH)
Gonads (LH/FSH)
Major function of hypothalamus
Releasing & inhibiting hormones
What is a neurosecretory cell?
Neurosecretory cell, a type of neuron, or nerve cell, whose function is to translate neural signals into chemical stimuli.
State hypothalamic hormone which controls secretion of LH/FSH?
GnRH Increases
- GnRH (Gonadotrophin releasing hormone )
Resistance to vitamin D?
Rickets
Lack of cortisol?
Addison’s disease
Complete resistance to circulating androgens?
Testicular feminisaiton
Andorgens= Present in both males and females, the principle androgens are testosterone and androstenedion
- Androgens are hormones that display male traits
State secretions of kidney?
Vit.D
EPO (erythropoietin)
State secretions in Parathyroid gland
Parathyroid hormone
Outline the pathway of how glands are affected by hypothalamic-pituitary axis
State 4 disorders of the endocrine system?
Excess or deficiency
Impaired synthesis
Transport and metabolism of hormones
Resistance to hormone action
State secretions of the bone?
Phosphate
Describe the intracrine signalling mechanism
Conversion of an inactive hormone into an active one
that acts within the cell
Describe the endocrine signalling mechanism
Hormones released by endo. cells into the general circulation (blood)
and acting on distant target sites
